Old versions of Java have been blocked - update and unblock Java | Troubleshooting

Old versions of Java have been blocked - update and unblock Java

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Firefox recently added older versions of the Java plugin to its blocklist causing it to be disabled. This was done because the old versions are vulnerable to an attack which could take over your computer without your knowledge and access files or steal critical information like banking credentials. This article describes the steps to update Java and get it working again.

Old versions of the Java plugin are vulnerable to an attack which could take over your computer without your knowledge and access files or steal critical information like banking credentials. This article describes the steps to update Java and get it working again.

Table of Contents

Update Java

Firefox only blocks vulnerable versions of Java so the thing to do is to update to latest version. Unfortunately, simply installing a new version of Java doesn't necessarily remove older Java versions from your computer which will leave you vulnerable. So you'll have to uninstall any old versions of Java before going ahead with the update.

At the top of the Firefox window, click on the Firefox button and then select ExitAt the top of the Firefox window, click on the File menu and then select ExitOn the menu bar, click on the Firefox menu and select Quit FirefoxAt the top of the Firefox window, click on the File menu and select Quit.

Click the menu button
and then click ExitQuit
.

From the Start Menu in the Windows taskbar, select Control Panel. The Control Panel opens.

Open the Windows program listing.

(Windows Vista/7) Click Programs and then Programs and Features.

(Windows 2000/XP) Double-click Add or Remove Programs.

From the list of currently installed programs, select any Java or Java Runtime programs.

To begin the uninstall:

(Windows Vista/7) Click Uninstall at the top of the window.

(Windows 2000/XP) Click Remove on the right of the Java listing.

Note: Complete the uninstall process before proceeding.

Run the installer you downloaded in step 1.

Start Firefox

Java should now work as expected.

Firefox only blocks vulnerable versions of Java so the thing to do is to update to latest version.

At the top of the Firefox window, click on the Firefox button and then select ExitAt the top of the Firefox window, click on the File menu and then select ExitOn the menu bar, click on the Firefox menu and select Quit FirefoxAt the top of the Firefox window, click on the File menu and select Quit.

Click the menu button
and then click ExitQuit
.

Run the installer you downloaded in step 1.

Start Firefox

Java should now work as expected.

The thing to do is to update to latest version.

At the top of the Firefox window, click on the Firefox button and then select ExitAt the top of the Firefox window, click on the File menu and then select ExitOn the menu bar, click on the Firefox menu and select Quit FirefoxAt the top of the Firefox window, click on the File menu and select Quit.

Click the menu button
and then click ExitQuit
.

From the Apple menu, select Software Update....

Select the Java update and click Install. Wait for the update to complete.

Start Firefox

Java should now work as expected.

If you had previously selected Disable in the blocking dialog, you may need to enable Java again:

At the top of the Firefox window, click on the Firefox buttonOn the menu bar, click on the Tools menuAt the top of the Firefox window, click on the Tools menu, and then click Add-ons. The Add-ons Manager tab will open.Click the menu button
and choose Add-ons. The Add-ons Manager tab will open.

In the Add-ons Manager tab, select the Plugins panel.

Find the Java Platform or Java Runtime item and click Enable.

Working around the blocklist

If you are unable to update Java and it's critical for you to continue using it, you can re-enable the blocked version.

Warning: This leaves you vulnerable to attacks. Simply browsing to a compromised website could result in your computer being exploited.

Enabling Java

At the top of the Firefox window, click on the Firefox buttonOn the menu bar, click on the Tools menuAt the top of the Firefox window, click on the Tools menu, and then click Add-ons. The Add-ons Manager tab will open.Click the menu button
and choose Add-ons. The Add-ons Manager tab will open.